A protein inhibitor of activated STAT (CgPIAS) negatively regulates the expression of ISGs by inhibiting STAT activation in oyster Crassostrea gigas. Issue 131 (December 2022)

• Record Type: Journal Article
• Authors: Wang, Sicong; Li, Yuanmei; Qiao, Xue; Jin, Yuhao; Liu, Rui; Wang, Lingling; Song, Linsheng
• Is Part Of: Fish & shellfish immunology. Issue 131(2022)
• Page Start: 1214
• Page End: 1223
• Publication Date: 2022-12
• Subjects: Crassostrea gigas -- PIAS -- STAT -- Negative regulation -- ISGs; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2022.11.020
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: The protein inhibitor of activated STAT (PIAS) family proteins act as the important negative regulators in janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, which can be also involved in regulating the expression of interferon-stimulated genes (ISGs). In the present study, a PIAS homologue (designated as Cg PIAS) was identified from oyster Crassostrea gigas . The open reading frame (ORF) of Cg PIAS cDNA was of 1887 bp encoding a peptide of 628 amino acid residues. The Cg PIAS protein contains a conserved scaffold attachment factor A/B/acinus/PIAS (SAP) domain, a Pro-Ile-Asn-Ile-Thr (PINIT) motif, a RING-finger-like zinc-binding domain (RLD) and two SUMO-interaction Motifs (SIMs). The deduced amino acid sequence of Cg PIAS shared 74.58–81.36% similarity with other PIAS family members in the RLD domain. The mRNA transcripts of Cg PIAS were detected in all the tested tissues with highest level in haemocytes (32.98-fold of mantles, p < 0.001). After poly (I:C) and recombinant Interferon-like protein (r Cg IFNLP) stimulation, the mRNA expression of Cg PIAS in haemocytes significantly up-regulated to the highest level at 48 h (7.38-fold, p < 0.001) and at 24 h (13.08-fold, p < 0.01), respectively. Moreover, the nuclear translocation of Cg PIAS was observed in haemocytes after poly (I:C) stimulation. Biolayer Interferometry (BLI) assay revealed that the recombinant protein Cg PIAS-RLD could interact with the recombinant protein Cg STAT in vitro with the KD value of 3.88 × 10 −8 M. In the Cg PIAS-RNAi oysters, the green signals of Cg STAT protein in nucleus of haemocytes increased compared with that in NC-RNAi group, and the mRNA expression of myxovirus resistance ( Cg Mx1), oligoadenylate synthase-like proteins ( Cg OASL), Cg Viperin and IFN-induced protein 44-like ( Cg IFI44L-1) in haemocytes significantly increased at 12 h after poly (I:C) stimulation, which were 2.39-fold ( p < 0.05), 2.18-fold ( p < 0.001), 1.74-fold ( p < 0.05), and 2.89-fold ( p < 0.01) of that in control group, respectively. The above results indicated that Cg PIAS negatively regulated the ISG expression by inhibiting STAT activation in oyster C. gigas . Highlights: The protein inhibitor of activated STAT ( Cg PIAS) was identified from C. gigas. Cg PIAS showed high expression level in haemocytes, gills and labial palps. Cg PIAS responded to Poly (I:C) and r Cg IFNLP stimulation. Cg PIAS negatively regulated the Cg ISGs expression by inhibiting STAT activation.